Some of the earliest recorded observations ever made through a telescope, Galileo's drawings on 28 December 1612 and 27 January 1613 contain plotted points that match up with what is now known to be the position of Neptune. On both occasions, Galileo seems to have mistaken Neptune for a fixed star when it appeared close—in conjunction—to Jupiter in the night sky; hence, he is not credited with Neptune's discovery. At his first observation in December 1612, Neptune was almost stationary in the sky because it had just turned retrograde that day. Because Neptune was only beginning its yearly retrograde cycle, the motion of the planet was far too slight to be detected with Galileo's small telescope.
Two hundred years later, Neptune continued to be elusive. By the middle of the 19th century, two scientists, one French and one English, working separately, had pinpointed the planet’s location in theory but neither could gain access to a large telescope to confirm it. If they had, they would have found it in precisely the predicted spot (in Aquarius). But neither of them had the wherewithal to make it happen. Finally, in 1846, one of them asked astronomers in Germany to undertake a search for the new planet. Johann Galle, a young assistant at the Berlin Observatory, found it within an hour.
Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet, and the densest giant planet. Neptune is seventeen times the mass of Earth, slightly more massive than its near-twin Uranus. Neptune is denser and physically smaller than Uranus because its greater mass causes more gravitational compression of its atmosphere. Neptune orbits the Sun once every 164.8 years. Neptune is not visible to the unaided eye.
The symbol of Neptune:
Neptune is named after the Roman god of the sea. Its symbol resembles that god’s three-pronged trident.
Assessing Neptune’s influence
Impressionistic Neptune rules intuition, dreams and visions, psychic ability, imagination, glamour, and everything that flows. Neptune finds expression in dance, music, poetry, and daydreams. It stimulates compassion, dissolves boundaries, and sensitizes anything it touches. Idealistic and deeply spiritual, it also has a dark side. Neptune is the planet of illusion, confusion, deceit, vagueness, and wishful thinking. When prominent in a positive way, Neptune brings artistic talent and imagination, spiritual leanings, and psychic abilities. Under negative conditions, it accentuates the tendency to drift and increases the danger of addiction, hypochondria, and escapism.
Neptune doesn’t affect everyone equally. Like the other outer planets, it tends to influence generations more strongly than individuals. But there are exceptions. How can you tell if you have a powerful Neptune? Neptune occupies a prominent position in your birth chart if:
i) It occupies an angle — that is, it’s in the first, fourth, seventh, or tenth house of your chart. It’s especially strong if it’s near your Ascendant or Midheaven.
ii) It makes a number of close aspects to other planets and, in particular, to the Sun, the Moon, or the planet that rules your Ascendant.
iii) You have one or more planets in Pisces.
Neptune spends an average of 14 years in each sign.
Neptune in the signs
Neptune’s position by sign describes the ways your generation is most idealistic — and most unrealistic. Its position in your horoscope represents an area of imagination, idealism, and spirituality (on the positive side), and aimless drifting, confusion, and deception (on the negative side). You can read more about Neptune in the Signs here!
Neptune in the Houses
The house that Neptune inhabits in your horoscope tells you where you can access the most profound level of intuition — and where you’re prone to deception. You can read more about Neptune in the Houses here!